The MULTISCREEN® Harvest Plate is a 96-well plate designed and optimized for cell harvesting applications. The plate is a single molded device having 96 distinct and separate wells into which is inserted a glass fiber mat filter which is used for retaining cells or other selected items. The plate has been well received, as its individual wells were specifically designed to have no cross talk between the wells.
The glass fiber disc was stuffed into each well such that the disc had an interference fit with the sides and/or bottom of the well. Lab tests of the plate were very successful, so the product was launched.
Unfortunately, the plate was not robust for all applications. It was learned that the plates are handled quite roughly, for example typically being loaded haphazardly into liquid filled drums. Many of the discs became dislodged as they were only held in by an interference fit.
Any dislodgment was unacceptable, so a means for securing the glass fiber disc had to be determined. Yet, the filter disc had to be secured without adding another molding step to minimize the cost and avoid the cross talk issue. As no other single-molded-plate was available on the market, no multiple-molded plate sold in the prior art offered a solution.
In two piece multiple well plates, e.g. those having a separate underdrain plate and a mating open welled top plate, the same means for securing the filter in the well has been used. When that has been found to be insufficient, other means such as ultrasonically welding the filter to one of the two components or using an O-ring above the filter have been tried. While these methods have worked to some degree they are slow, costly and time consuming.
Accordingly, it was desirable to provide a multiple well plate, whether a single molded design or a two piece design, that had its filtration material secured therein such that it did not come dislodged during usage.
In addition, it would be desirable to provide a process for making such plates.